• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1620-1628
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• 2016

In this study, we investigated colistin resistance mechanisms associated with the regulation of the pbgP operon in Klebsiella pneumoniae, using four isogenic pairs of colistin-susceptible strains and their colistin-resistant derivatives and two colistin-resistant clinical isolates. Amino acid sequence alterations of PhoPQ, PmrAB, and MgrB were investigated, and mRNA expression levels of phoQ, pmrB, pmrD, and pbgP were measured using quantitative real-time PCR. The phoQ and pmrB genes were deleted from two colistin-resistant derivatives, 134R and 063R. We found that phoQ, pmrD, and pbgP were significantly upregulated in all colistin-resistant derivatives. However, pmrB was significantly upregulated in only two colistin-resistant derivatives and one clinical strain. pmrB was not overexpressed in the other strains. The minimum inhibitory concentration of colistin was drastically lower in both phoQ- and pmrB-deleted mutants from a colistin-resistant derivative (134R) that was overexpressing phoQ and pmrB. However, colistin susceptibility was restored only in a phoQ-deleted mutant from a colistin-resistant derivative (063R) without overexpression of pmrB. In conclusion, two different regulations of the pbgP operon may associate with the development of colistinresisant K. pneumoniae.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권4호
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• pp.234-241
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• 2000

The Saccharomyces cerevisiae PMR1 gene encodes a Ca2+-ATPase localized in the Golgi. We have investigated the effects of PMR1 disruption in S. cerevisiae on the glycosylation and secretion of three heterologous glycoproteins, human ${\alpha}$1-antitrypsin (${\alpha}$1-AT), human antithrombin III (ATHIII), and Aspergillus niger glucose oxidase (GOD). The pmr1 null mutant strain secreted larger amounts of ATHIII and GOD proteins per a unit cell mass than the wild type strain. Despite a lower growth rate of the pmr1 mutant, two-fold higher level of human ATHIII was detected in the culture supernatant from the pmr1 mutant compared to that of the wild-type strain. The pmr1 mutant strain secreted ${\alpha}$1-AT and the GOD proteins mostly as core-glycosylated forms, in contrast to the hyperglycosylated proteins secreted in the wild-type strain. Furthermore, the core-glycosylated forms secreted in the pmr1 mutant migrated slightly faster on SDS-PAGE than those secreted in the mnn9 deletion mutant and the wild type strains. Analysis of the recombinant GOD with anti-${\alpha}$1,3-mannose antibody revealed that GOD secreted in the pmr1 mutant did not have terminal ${\alpha}$1,3-linked mannose unlike those secreted in the mnn9 mutant and the wild type strains. The present results indicate that the pmr1 mutant, with the super-secretion phenotype, is useful as a host system to produce recombinant glycoproteins lacking high-mannose outer chains.

• 대한본초학회지
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• 제30권2호
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• pp.11-18
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• 2015

Objectives : Polygoni Multiflori Radix (Jeokhasuo in Korean) is a Oriental traditional herbs widely used in East Asian countries. Overconsumption of fructose results in hypertension, dyslipidemia, obesity and impaired glucose tolerance which have documented as a risk of cardiovascular diseases. This experimental study was designed to investigate the beneficial effects of an ethanol extract from Polygoni Multiflori Radix (PMR) in high-fructose (HF) diet-induced metabolic syndrome rat model. Methods : Sprague-Dawley (SD) rats were divided into three groups; Control group, receiving regular diet and tap water, HF group, and HF + PMR group both receiving supplemented with 65% fructose (n=10), respectively. The HF + PMR group initially received HF diet with PMR (100 mg/kg/day) for 8 weeks. Results : PMR significantly prevented the metabolic disturbances such as hyperlipidemia, hypertension and impaired glucose tolerance. Chronic treatment with PMR significantly decreased body weight, fat weight and adipocyte size, suggesting a role of anti-obesity effect. PMR led to improve the hyperlipidemia through the increase in HDL cholesterol level as well as the decrease in triglyceride and LDL cholesterol level. In addition, PMR suppressed adhesion molecules and endothelin-1 (ET-1) expression in aorta resulting in the decrease of hypertension. In muscle tissue, PMR significantly recovered the HF-induced insulin resistance through increase of insulin receptor substrate-1 (IRS-1), p-$AMPK{\alpha}1/2$, and p-Akt expression. PMR improved HF-induced metabolic disorders and its action was caused by energy metabolism-mediated insulin signaling activation. Conclusions : These results demonstrate that PMR may be a beneficial therapeutic for metabolic syndrome through the improvement of hyperlipidemia, obesity, insulin resistance and hypertension.

• 접착 및 계면
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• 제4권1호
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• pp.1-8
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• 2003

본 연구에서는 이관능성 에폭시와 PMR-15 블렌드계의 접촉각 측정과 파괴인성 측정을 통하여 PMR-15 조성비에 따른 표면자유에너지가 기계적 계면특성에 미치는 영향에 대하여 고찰하였다. 블렌드계의 FT-IR 분석 결과, PMR-15의 이미드화에 따른 특성 밴드가 1,722, $1,778cm^{-1}$ (C=O)와 $1,372cm^{-1}$ (C-N)에서 나타났고, 에폭시의 개환 반응에 따른 -OH peak는 PMR-15 phr의 함량에서 가장 크게 나타나는 것을 확인할 수 있었다. 증류수와 diiodomethane을 젖음액으로 사용하여 sessile drop 방법으로 접촉각을 측정한 결과, 표면자유에너지는 극성 요소의 증가에 의해서 PMR-15의 함량이 10 phr일 때 최고값을 나타내었다. 또한, 기계적 계면특성을 파괴인성 측정을 통하여 알아본 결과 $K_{IC}$와 $G_{IC}$ 또한 표면자유에너지와 유사한 경향을 나타내는 것을 알 수 있었는데, 이는 PMR-15 10 phr의 조성에서 수소결합의 증가에 의한 블렌드계의 극성요소가 증가함에 따라 분자들간의 계면결합력이 증가했기 때문인 것으로 관찰된다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 추계학술발표대회 논문집
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• pp.265-268
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• 2002

In this work, the blend system of epoxy and PMR-15 polyimide is investigated in terms of the cure behaviors and thermal stabilities. The cure behaviors are studied in DSC measurements and thermal stabilities are also carried out by TGA analysis. DDM (4, 4'-diamino diphenyl methane) is used as curing agent for EP and the content of PMR-15 is varied within 0, 5, 10, 35, and 20 phr to neat EP. As a result, the cure activation energy ($E_a$) is increased at 10 phr of PMR-15, compared with that of neat EP. From the TGA results of EP/PMR-15 blend system, the thermal stabilities based in the initial decomposed temperature (IDT) and integral procedural decomposition temperature (IPDT) are increased with increasing the PMR-15 content. The fracture toughness, measured in the context of critical stress intensity factor ($K_{IC}$) and critical strain energy release rate ($G_{IC}$), shows a similar behavior with $E_a$. This result is probably due to the crosslinking developed by the interactions between intermolecules in the polymer chains.

• 한국임상수의학회지
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• 제28권4호
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• pp.375-386
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• 2011

Polygoni Multiflori Radix (PMR), a dried root tuber of Polygonum multiflorum Thunberg with bioactivities in bone metabolism is one of the most famous tonic traditional medicines. To observe in vivo anti-osteoporotic efficacy of PMR extracts, we orally administered once a day for 28 days (Qd ${\times}$ 28) to bilateral ovariectomized (OVX)-induced osteoporosis ddY mice after 1 week of recovery periods at 125, 250 and 500 mg/kg (of body weight). A positive control drug, Alendronate (FOSA) 10 mg/kg-dosing group was added. As results of OVX-induced osteoporotic process, estrogen-deficient osteoporotic changes were also dramatically decreased in all PMR extracts-dosing groups. Especially middle dosage of PMR extracts, 250 mg/kg constantly and significantly (p < 0.01 or p < 0.05) inhibited the loss of bone strength and bone quality. Based on the results, it was concluded that PMR extracts (125, 250 or 500 mg/kg; orally dosing) has relatively good favorable effect to prevention and/or treatment of OVX-induced osteoporosis. Therefore, although the efficacy was slighter than that of Alendronate on the inhibition of bone loss, it is expected that PMR extracts will be promising as a new anti-osteoporotic agents for prevent the fracture induced in osteoporotic patients because natural herbal medicine origin PMR extracts will be dose not show serious side effects especially the problem in upper alimentary irritation by bisphosphonate and hypercalcaemia of parathyroid hormone analogs.

• 대한본초학회지
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• 제30권3호
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• pp.77-82
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• 2015

Objectives : The Korean medical doctors use PMR(Polygoni Multiflori Radix) for nourishing the liver-kidney, loosing the bowel to relieve constipation, recovering from malaria, and clearing away heat and eliminating toxin, etc. But, this study was performed to investigate the effect of water extracts from PMR on prevention of hyperlipidemia and liver damage induced by alcohol. Methods ： Except for the normal group, we fed rat on 25% alcohol for 55 days. And the extract was administrated for the same period. We measured the serum components in rat's blood, body weight and weight of liver. Results ： At first, we observed effects of PMR on prevention of hyperlipidemia induced by alcohol. PMR group showed significant decrease of total cholesterol and triglyceride in comparison with those of the control group. PMR group showed significant increase of body weight in comparison with those of the control group in 4weeks and 8weeks. At second, we observed effects of PMR on prevention of liver damage induced by alcohol. PMR group showed significant decrease of GOT, GPT, ALP, and LDH in comparison with those of the control group. PMR group showed significant increase of liver weight in comparison with those of the control group. Conclusions ： Reviewing these experimental results, it appears that water extracts from PMR have pharmaceutical efficacy on prevention of hyperlipidemia and liver damage induced by alcohol. Therefore further additional study should be conducted to elucidate in depth the pharmaceutical efficacy of these.

• Journal of Applied Biological Chemistry
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• 제65권4호
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• pp.287-298
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• 2022

본 연구는 증자, 숙성 및 발효에 따른 Polygoni multiflori Radix의 이화학적 특성, phytochemical 함량, 영양성분 및 항산화 활성 변화를 확인하였다. Polygoni multiflori Radix (PMR)은 가공 후 pH는 약간 감소하고 산도는 증가하였다(pH 5.70→4.78, 산도 0.23→0.29%). 환원당 함량은 숙성과 발효 후 PMR (1.19mg/g)에서 1.40 (FPMR), 1.30 (RPMR), 1.53 (FRPMR), 1.99 (BPMR) 및 2.33 mg/g (FBPMR)으로 증가하였다. Total phenolic 함량은 PMR (6.05 mg/g)에서 가장 높았으며, total flavonoid 함량과 maillard product는 PMR을 숙성과 발효 후 증가하였으며 각각 BPMR (1.60 mg/g)과 FBPMR (2.76 O.D.)에서 가장 높았다. 주요 phytochemical은 2,3,5,4'-tetrahydroxystilbene-2-0-α-glucoside로 PMR (64.9 mg/g)에서 가장 높았으며, FPMR에서 46.47 mg/g, RPMR에서 33.94 mg/g, FRPMR에서 48.76 mg/g, BPMR에서 36.68 mg/g, FBPMR에서 34.35 mg/g이 검출되었다. 주요 지방산과 유리아미노산은 palmitic acid(C16:0)과 proline이었다. 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt 라디칼 소거활성 및 FRAP 환원력은 대체로 PMR(39.06%, 98.32%, 및 2.61 O.D. - 추출물 농도 1.0 mg/mL)에 가장 높은 활성을 보였으며 숙성과 발효 후에 감소하는 경향을 보였다.

• 한국임상수의학회지
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• 제28권4호
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• pp.387-393
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• 2011

Polygoni Multiflori Radix (PMR) a dried root tuber of Polygonum multiflorum Thunberg with bioactivities in bone metabolism is one of the most famous tonic traditional medicines in China, Japan and Korea.To observe the anti-osteoporotic effect of PMR, we observed the effects on proliferation and alkaline phosphatase (ALP) activity of primary osteoblasts, bone nodule formation, pit formation of osteoclasts and osteoclastogenesis in vitro. As the result of that, although PMR extracts have no meaningful changes on the the proliferation of primary osteoblasts, significant (p < 0.01) increases of ALP acitivity of osteoblasts were dose-dependently observed in all PMR extracts treated groups tested compared to that of vehicle control. It means that it enhanced the differentiation (ALP activity) and bone nodule formation of osteoblast. In addition, PMR extracts dose-dependently inhibits the pit formation and the number of multinucleated osteoclast-like cells (OCLs), osteoclastogenesis in vitro. Therefore these results show the possibility of PMR extracts as another anti-osteoporotic agents.

• 전기전자학회논문지
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• 제27권3호
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• pp.319-326
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• 2023

본 논문에서는 단상 전압 소스 인버터 (VSIs)의 강인한 출력 전압 제어를 위한 디지털 제어기 구현과 총 고조파 왜곡(T.H.D.v) 분석을 포함한 시뮬레이션 및 실험 결과를 제시한다. 일반적으로 VSI는 내부 루프의 전류 제어기에 비례 적분(PI) 제어기를 사용하고 외부 루프의 전압 제어기에 비례 공진 (PR) 제어기가 사용된다. 그러나, 비선형 부하에서 여전히 3차, 5차 및 7차와 같은 고차 고조파 왜곡이 발생한다. 따라서 본 논문에서는 고조파 왜곡을 억제하기 위해 홀수 고조파 주파수에 대한 공진 제어기를 포함한 비례 다중 공진 (PMR) 제어기를 제안한다. VSI 플랜트용 컨트롤러의 주파수 응답을 분석하고 PMR 컨트롤러를 설계합니다. 시뮬레이션을 통해 PI와 PMR을 전압 제어기로 사용할 때 출력 전압의 총 고조파 왜곡 특성을 비교 검증합니다. 선형 및 비선형 하중 조건이 모두 고려되었습니다. 마지막으로 PMR 제어기를 3kW급 VSIs 프로토 타입에 적용하여 그 유효성을 입증하였다.